Heart rhythm irregularities during laparoscopy: Description of a novel technique to manage severe intra-operative bradycardia - A case report

Abstract

Introduction & importance

Minimally invasive abdominal surgeries need insufflation of a gas (usually carbon dioxide) into the peritoneal cavity for creating a pneumoperitoneum. Laparoscopic techniques have its own set of inherent complications. In order to maintain the operative space, constant gas flow is required to assist various surgeries. Increase in intraabdominal pressure due to high flow rate of gas during peritoneal insufflation is considered to be a probable cause of intraoperative vagal-mediated bradycardia resulting due to stretching of peritoneum. Intraoperative bradycardia during laparoscopic surgery can potentially lead to cardiac arrest and untoward outcomes.

Case presentation

We report a case of a middle-aged hypertensive, hypothyroid patient with history of angle closure glaucoma who was undergoing elective laparoscopic cholecystectomy after proper pre-operative anesthesia/ physician and Ophthalmology clearance. Patient underwent general anesthesia (GA) and developed severe sinus bradycardia after insufflation, during stretch over gall bladder. Insufflation was stopped and abdomen deflated immediately. In view of glaucoma, atropine was contraindicated. 10 mL of 1% lignocaine was infiltrated into Calot's triangle and peri-gallbladder area. Surgery was resumed after 5 min and completed laparoscopically.

Clinical discussion

Bradycardia can occur during laparoscopic surgery mostly during rapid inflow of gas leading to peritoneal stretching with the added effect of vagotonic drugs used for general anesthesia. Use of intraperitoneal local anesthesia drugs for postoperative pain has been thoroughly studied and recommended due to statistically significant reduction in early postoperative abdominal pain. The management of intraoperative bradycardia should be prompt as it may be an early warning for cardiac arrest.

Conclusion

Vagal response following creation of pneumoperitoneum for minimally invasive abdominal surgeries is thought to be the most common cause for bradycardia. The effect of local anesthetic infiltration into peritoneum to reduce post operative pain is probably be due to blockade of afferent nerve endings in the peritoneum. Local anesthesia infiltration into Calot's triangle can be safely administered to mitigate localised vagal reflex.

Highlights

• •Knowledge about effects of pneumoperitoneum has gained importance with use of minimally invsive surgery worldwide.
• •Pneumoperitoneum causes hemodynamic and cardiovascular changes in patients during and after laparoscopic procedures.
• •Heart rhythm abnormalities during laparoscopy are a known complication and prompt intervention is required to avoid adverse outcomes.
• •Anticholinergics are the first line of treatment, though patient may need temporary or permanent pacing.

1. Introduction

Laparoscopic surgery is now a preferred technique for a range of surgical procedures including cholecystectomy, appendectomy, hernioplasty and advanced surgeries like colorectal, pancreatic, urological and metabolic surgeries. Being minimally invasive, laparoscopy offers benefits of reduced post-operative pain, wound size, reduced tissue trauma, better post-operative pulmonary function, early mobility and recovery, shorter hospital stay, and reduced health costs.

However, laparoscopy is not immune to complications and various intraoperative complications intrinsic to laparoscopic surgery have been reported including vascular injury, gas embolism, arrhythmias and cardiac arrest [1]^, [2].

Creation of a pneumoperitoneum using carbon dioxide insufflation at a rate of 4–6 L/min to a pressure of 10–15 mm Hg is necessary to separate the abdominal wall from the abdominal viscera to improve visualization during surgery [3].

The effect of abdominal distension on vagal tone during pneumoperitoneum is thought to be the most common cause for intra-operative bradycardia [4]. Serious intra-operative bradycardia leading to cardiac arrest has been reported to occur in 2 and 40 per 100,000 laparoscopic surgeries.

The management of intra-operative bradycardia should be prompt and definitive as it could be a sentinel warning for a major cardiac catastrophe. The usual management includes prompt cessation of surgery, cessation of gas inflow, deflation of pneumoperitoneum, intravenous atropine administration followed by lowering of preset intra-abdominal pressure, flow rate before resuming surgery.

The work has been reported in line with the SCARE criteria [5].

2. Presentation of case

A 58 year female patient with BMI 27.05 kg/m² (height 155 cm, weight 65 kg) was admitted to our hospital for laparoscopic cholecystectomy. The patient pre-operative assessment in the anesthesia clinic done was normal with prior history of hypertension on regular antihypertensives (Telmisartan+Hydrochlorthiazide), primary hypothyroidism on LT4 replacement (50 μg/daily), acute angle closure glaucoma diagnosed 4 months ago on topical bimatoprost, timolol and brimonidine with surgical H/o hysterectomy - 10 years ago. Pre-operative baseline investigations were all within normal limits. Ophthalmology consultation was done, IOP checked was normal. Baseline HR and NIBP were 70 bpm & 140/80 mm Hg respectively with normal sinus rhythm, RR 14/min. Anesthesia premedication given inj midazolam (1 mg), induction of anesthesia with inj. fentanyl (100 μg), inj. propofol (100 mg), and neuromuscular blockade using inj atracurium (25 mg). LMA I-gel No 4 placed and RT inserted. Adequate depth of anesthesia was maintained with isoflurane maintaining at minimum alveolar concentration (MAC) of 1 throughout the procedure. Patient was ventilated on volume control mode with peak airway pressure <30 cm H₂0 and EtCO₂ between 35 and 40 mm Hg. Pneumoperitoneum using CO₂ was created with Veress technique with flow rate of 2 L/min. Standard 4 ports were placed after port site local anesthesia (LA) infiltration (1% lignocaine) as a standard procedure and CO₂ flow rate adjusted @ 10 L/min with a preset IAP of 14 mm Hg as a standard procedure. Sudden sinus bradycardia (HR 32/min) was noticed after few minutes, surgeons were alarmed, pneumoperitoneum was desufflated immediately. Reverse Trendelenburg position was reverted back to supine, IV fluids were rushed to improve preload to prevent reflex bradycardia. Patient's heart rate started to increase steadily and reached to 60–70 bpm. O₂ saturation, EtCO₂, and BP were normal all the time. After stabilisation of patient re-attempt was planned, preset IAP was reduced from 14 mm Hg to 10 mm Hg and pneumoperitoneum was created. Patient developed bradycardia while stretch was applied over gall bladder (GB) to start Calot's dissection. Abdomen was desufflated again till HR was back to normal. Before 3rd attempt to resume surgery, the flow rate was reduced from 10 to 07 L/min and IAP maintained at 10 mm Hg and surgery resumed. Patient again developed severe sinus bradycardia (HR 30/min) after GB was pulled. Procedure was stopped till HR resumed to normal. The depth of anesthesia was adequately controlled at all times maintaining the MAC >1. In view of angle closure glaucoma atropine and other anticholinergic drugs were contraindicated due to their mydriatic effect and precipitation of attack of glaucoma with probable vision loss. Cardiologist was consulted for possible intraoperative pacing or abandoning the procedure if permanent pacing required. External pacemaker pads were applied on patient and pacing sheath & wires kept as standby. 10 mL of 1% lignocaine was infiltrated into Calot's triangle and peri-GB area with patient kept in reverse Trendelenburg position. Surgery was resumed after 5 min and completed laparoscopically in 65 min with stable hemodynamic status and heart rate >50 bpm throughout the procedure. At the end of the procedure, neuromuscular blocked was reversed with neostigmine (3.5 mg) and the LMA removed. Postoperative period remained uneventful. Pilocarpine and brimonidine eye drops were continued in post operative period. ECG was repeated, normal. Patient was discharged on POD 1 with no perioperative complications.

3. Discussion

Laparoscopic surgeries start with creation of pneumoperitoneum using closed Veress or open Hassan's techniques with insufflation of gas usually carbon dioxide (CO₂) to attain an intraabdominal pressure (IAP) of 12 to 15 mm Hg. Two main factors of capnoperitoneum which have pathophysiological effect on cardiovascular, respiratory, and renal systems include increased IAP and hypercarbia [6]. Raised IAP may lead to various intraabdominal changes like inferior vena cava compression, aortic compression, reduced splanchnic blood flow, decreased renal blood flow and displacement of diaphragm [7].

Effect of vagal response during laparoscopic surgeries leading to reflex bradycardia is a well-known entity [8]. Due to the stretching effect of abdominal insufflation on peritoneum, the vagal tone increases which in turn lead to bradyarrhythmias and asystole [9]. Intraoperative bradycardias have an incidence of ranging from 3.4 to 28% [10]. Bradycardia occurring during insufflation of gas is not inevitably a benign event as it may be a sentinel sign for an imminent and unforeseen cardiac arrest.

Various factors might be involved for intraoperative bradyarrhythmias like vagal stimulation, drugs (sympatholytics, calcium channel blockers, beta-blockers, opioids), hypothyroidism, hypothermia, endotracheal suctioning, and increased IAP [11]. Thus the challenges for preventing and managing such untoward incidents during laparoscopic surgeries and thereby avoiding forthcoming adverse consequences with the patients under anesthesia persist. Although modern day general anesthesia is considered safe, however GA increases vagal tone, especially when establishing induction with combination of propofol, vecuronium and fentanyl. Fentanyl decreases the sympathetic tone and enhances vagal tone with added effect with the simultaneous use of vecuronium, leading to bradycardia and possible cardiac arrest [12].

Most of the intraoperative bradycardia events respond well to the anticholinergics and cessation of insufflation, deflation of pneumoperitoneum which implies role of vagal reflex for the underlying mechanism. Premedication with glycopylorate, lower insufflation rate and keeping Low IAP can reduce the vagal effect and preclude cardiovascular changes and forthcoming cardiac events [3]^, [14].

The effect of local anesthetic infiltration at port sites and intraperitoneally has been studied by various authors to reduce post operative pain with a possible explanation of afferent nerve and vagal endings blockade in the peritoneum [15]. Few authors have suggested that there is an important role of the timing of LA infiltration in the success of the technique [16]. It has been argued that postoperative pain is less in subjects when LA administration occurs before the pain pathways are activated as compared to administration afterwards due to suppression of central neural sensitization by intraperitoneal infiltration.

Bindra et al. demonstrated that if analgesia is given before a painful stimulus, it reduces the level of neural sensitization. The study concluded that administration of intraperitoneal ropivacaine before insufflation leads to a significant decrease in postoperative pain scores as compared to intraperitoneal ropivacaine infiltration after surgery [17]. Boddy et al. concluded that intraperitoneal administration of local anesthetic agents is safe and shows statistically significant decrease in early postoperative pain scores [18].

Yi SQ et al. [19] studied the surgical anatomy of nervous innervation of gallbladder in humans. They demonstrated that the gallbladder and its liver bed have sympathetic and parasympathetic innervation through the anterior and posterior hepatic plexus, and phrenic nerve. The hepatic plexuses arise from the hepatic branches of the celiac plexus and vagus nerve and pass through the hepatoduodenal ligament. The nerves supplying the gallbladder pass along cystic duct and cystic arteries.

4. Conclusion

Bradycardia occurs during laparoscopic surgery, and mostly during peritoneal stretching, with the contribution from vagotonic drugs used for general anesthesia. Anticipation and prophylactic anticholinergic use in selected cases, seriousness regarding the procedure, vigilant monitoring, and prompt action are emphasized.

Communicating with the surgeon to immediately cease the surgical stimulus, interrupt the carbon dioxide insufflation and deflate the pneumoperitoneum, concurrently with atropine administration relieves bradycardia and possibly prevents its progression to cardiac arrest.

Use of intraperitoneal local anesthesia is safe, and it results in a statistically significant reduction in early postoperative abdominal pain. Local infiltration of LA into Calot's triangle can be safely administered to mitigate localised vagal reflex.

Consent

Written informed consent was obtained from the patient for the publication of this case report and accompanying images. A copy of the written consent is available for the review by the Editor-in Chief of this journal on request.

Ethical approval

Ethical approval was provided by the authors institution regarding publication and maintaining the non-disclosure of identity of patient.

Funding

No funding received for the work reported.

Guarantor

Dr JP Singh.

Research registration number

First in man study - not applicable.

CRediT authorship contribution statement

• 1.Dr Suhail Khuroo - Conceptualised the case report and drafted the manuscript
• 2.Dr Kuldeep Raina - Literature review and drafting of manuscript
• 3.Dr Ajaz Ahmad Wani - Literature review and drafting of manuscript
• 4.Dr Farzana Feroze - Review of literature and drafting of discussion.

Declaration of competing interest

The authors declare no competing interests.